I was wondering if you have had any cases where the Users Online module caused a site to malfunction with it DNN scheduler. We've had errant modules in the past that interact with scheduler do this. Our site is now experiencing problems staying up since installing the module.

It is not likely to be caused by the module it's self, but that the DNN version you are using has some issues with the scheduler it's self.

There are several issues with the scheduler process in several versions of DNN. In some versions of DNN the timer scheduler will just never work at all.

The good news is that the fix is easy. Just update DNN to a version with no issues in this area. We suggest at this time DNN 4.9.5 (min 4.9.4). DNN 5 is ok as a second choice, but we see a few additional problems with the latest version.

Ok, we have not seen problems with DNN 4.9.5 and scheduler, but we have seen other scheduler processes fail and bring down other processes.

Easy solution is to disable them all, then one by one enable again and check they finish their process correctly. This usually fixes things. Mostly it is caused by coming from a version that had issues, then when you upgrade there is a baxklog of things to be done and stuff fails.